First post and could use a little help. I bought a new model 16 trophy hunter package in 6.5 creedmoor. I shot a couple of rounds and then noticed what looks like an odd gap or a part missing. No pic on the Savage website looks like my rifle. I did search the box and finally found a C shaped part with a set screw. As a new member I can't post a pic but looking at the manual the uninstalled part is 12b, the rear baffle on the bolt. What does it do and how could this rifle have made it out of final inspection? Can I install it myself and will it be safe? Thanks.